Abstract: A phase change memory device includes a phase change memory cell block having alternating odd-numbered and even-numbered local bit lines, a global bit line, a plurality of first bit line selection circuits, and a plurality of second bit line selection circuits. The plurality of first bit line selection circuits are located at a first side of the phase change memory cell block and selectively connect respective odd-numbered local bit lines to the global bit line. The plurality of second bit line selection circuits are located at second side of the phase change memory cell block (opposite the first side) and selectively connect respective even-numbered local bit lines to the global bit line.

Abstract: A semiconductor memory device, which has an array of memory cells connected with a plurality of bit line pairs and a plurality of word lines, to perform a read or write operation of data, having low power consumption is provided. The device includes a first power supply for supplying a first power source voltage. Also, a second power supply supplies a second power source voltage having a lower voltage level than the first power source voltage. Further, the device includes a standard ground. An elevated ground circuit provides an elevated ground voltage having a higher voltage level than that of the standard ground. A first power circuit is connected with the first power supply and the standard ground, and operates in response to the first power source voltage. A second power circuit is connected with the second power supply and the elevated ground circuit, and operates in response to the second power source voltage. Thereby, power and chip size can be reduced.

Abstract: A phase change memory device includes a memory array including a plurality of phase change memory cells, each phase change memory cell including a phase change material and a diode, a plurality of column selection transistors connecting bit lines connected to the phase change memory cells to corresponding data lines, and a control node connecting the data lines to a sense amplifier unit. In a write operation mode, control voltages obtained by boosting a first voltage are respectively applied to the control node and gates of the column selection transistors, and a ground voltage is applied to a word line of a selected one of the phase change memory cells. In a standby mode, word lines and bit lines connected to the phase change memory cells of the memory array are maintained at the same voltage.

Abstract: A magnetic memory device includes a common line; a first write-in diode, a readout diode and a second write-in diode being connected to the common line in parallel. The magnetic memory device further includes a magnetic tunnel junction structure connected to the readout diode, first and second write-in conductors disposed at both sides of the magnetic tunnel junction structure and connected to the first and second write-in diodes, respectively and a first write-in line, a readout line and a second write-in line, which are connected to the first write-in conductor, the magnetic tunnel injection structure, and the second write-in conductor, respectively.

Abstract: A phase change memory device of one aspect includes a memory array including a plurality of phase change memory cells, a write boosting circuit, and a write driver. The write boosting circuit boosts a first voltage and outputs a first control voltage in response to a control signal in a first operation mode, and boosts the first voltage and outputs a second control voltage in response to the control signal in a second operation mode and a third operation mode. The write driver is driven by the first control voltage in the first operation mode and writes data to a selected memory cell of the memory array.

Abstract: A phase change memory device includes a phase change memory cell block having alternating odd-numbered and even-numbered local bit lines, a global bit line, a plurality of first bit line selection circuits, and a plurality of second bit line selection circuits. The plurality of first bit line selection circuits are located at a first side of the phase change memory cell block and selectively connect respective odd-numbered local bit lines to the global bit line. The plurality of second bit line selection circuits are located at second side of the phase change memory cell block (opposite the first side) and selectively connect respective even-numbered local bit lines to the global bit line.

Abstract: A phase-change cell memory device includes a plurality of phase-change memory cells, an address circuit, a write driver, and a write driver control circuit. The phase-change memory cells each include a volume of material that is programmable between amorphous and crystalline states. The address circuit selects at least one of the memory cells, and the write driver generates a reset pulse current to program a memory cell selected by the address circuit into the amorphous state, and a set pulse current to program the memory cell selected by the address circuit into the crystalline state. The write driver control circuit varies at least one of a pulse width and a pulse count of at least one of the reset and set pulse currents according to a load between the write driver and the memory cell selected by the address circuit.

Abstract: A firing method of a phase change memory device and a phase change memory capable of effectively performing a firing operation are described. The phase change memory device includes a plurality of memory cell array blocks, a counter clock generation unit, a decoding unit, and a driving unit. Each memory cell array block has phase change memory cells. The counter clock generation unit outputs first through third counter clock signals in response to an external clock signal and a firing mode signal, wherein the first through third counter clock signals have different cycles. The decoding unit, in response to the first through third counter clock signals, outputs a block address which selects one of the plurality of memory cell array blocks, word line addresses which enable word lines of the selected memory cell array block, and a redundant word line address which enables a redundant word line of the selected memory cell array block.

Abstract: Phase-changeable random access memory (PRAM) devices include a plurality of rows and columns of PRAM memory cells therein and at least one local bit line electrically coupled to a column of the PRAM memory cells. First and second bit line selection circuits are provided to increase the rate at which the at least one local bit line can be accessed and driven with a bit line signal. These first and second bit line selection circuits are configured to electrically connect first and second ends of the at least one local bit line to a global bit line during an operation to read data from a selected one of the PRAM memory cells in the column.

Abstract: A semiconductor memory device of one aspect includes a memory cell block including n global word lines, and corresponding m sub word lines for each of the n global word lines, where n and m are natural numbers. The memory device further includes a plurality of word line driving circuits which respectively control a voltage of the sub word lines according to a logic level of each corresponding global word line and inputted address signals, and a plurality of control circuits which transmit the address signals to the word line driving circuits or interrupt transmission of the address signals according to the logic level of the global word line. Each of the word line driving circuits includes a first transistor which maintains the voltage of the respective sub word line at a first voltage and a second transistor which maintains the voltage of the sub word line at the first voltage or a second voltage.

Abstract: A phase-change cell memory device includes a plurality of phase-change memory cells, an address circuit, a write driver, and a write driver control circuit. The phase-change memory cells each include a volume of material that is programmable between amorphous and crystalline states. The address circuit selects at least one of the memory cells, and the write driver generates a reset pulse current to program a memory cell selected by the address circuit into the amorphous state, and a set pulse current to program the memory cell selected by the address circuit into the crystalline state. The write driver control circuit varies at least one of a pulse width and a pulse count of at least one of the reset and set pulse currents according to a load between the write driver and the memory cell selected by the address circuit.

Abstract: Phase change memory devices having cell diodes and related methods are provided, where the phase change memory devices include a semiconductor substrate of a first conductivity type and a plurality of parallel word lines disposed on the semiconductor substrate, the word lines have a second conductivity type different from the first conductivity type and have substantially flat top surfaces, a plurality of first semiconductor patterns are one-dimensionally arrayed on each word line along a length direction of the word line, the first semiconductor patterns have the first conductivity type or the second conductivity type, second semiconductor patterns having the first conductivity type are stacked on the first semiconductor patterns, an insulating layer is provided on the substrate having the second semiconductor patterns, the insulating layer fills gap regions between the word lines, gap regions between the first semiconductor patterns and gap regions between the second semiconductor patterns, a plurality of p

Abstract: A method of biasing a memory cell array during a data writing operation and a semiconductor memory device are provided. The semiconductor memory device includes: a memory cell array including a plurality of memory cells in which a first terminal of a memory cell is connected to a corresponding first line among a plurality of first lines and a second terminal of a memory cell is connected to a corresponding second line among a plurality of second lines; and a bias circuit for biasing a selected second line to a first voltage and non-selected second lines to a second voltage.

Abstract: A redundancy circuit in a semiconductor memory device having a multiblock structure in which a memory cell array is classified into a plurality of memory cell blocks, an integrated redundancy circuit having a plurality of fuse boxes for storing, per block, addresses of defective memory cells provided in the plurality of memory cell blocks, the plurality of fuse boxes being connected to the common precharge unit and being selectively activated in response to a block distinction selection signal.

Abstract: A reference voltage generating circuit includes a current mirror circuit having first and second current paths formed between a first power source terminal and a second power source terminal in which the current mirror circuit is operated in response to a voltage level of the second current path, a reference voltage output node for providing a reference voltage and being located on the second current path, an active resistance device formed on the first current path to be operated in a linear region of a current-voltage characteristic curve of the active resistance device, and a voltage supply circuit for supplying the active resistance device with an enable voltage to control the active resistance device to be operated in the linear region.

Abstract: A true bit line can extend across a memory cell area of the memory device in a first direction and a complementary bit line can extend across the memory cell area in a second direction opposing the first direction, wherein the true bit line and the complementary bit line comprising a bit line pair.

Abstract: Disclosed are a semiconductor memory device and a method of programming the same. The semiconductor memory device comprises a plurality of memory cells, each of the memory cells having a plurality of phase change variable resistors and a selection transistor. Each of the phase change variable resistors has a first end connected to one of a plurality of bit lines and a second end connected to a drain of the selection transistor. The selection transistor has a gate connected to a word line and a source connected to a reference voltage. The memory device is programmed by activating a word line associated with a selected memory cell, thereby turning on the selection transistor, applying a reset pulse to bit lines of the selected memory cell, and applying a set pulse to selected bit lines of the selected memory cell.

Abstract: A semiconductor memory device compensates leakage current. A plurality of memory cells is disposed at intersections of word lines and bit lines. A plurality of dummy cells is connected to at least one dummy bit line. A leakage compensation circuit is connected to the at least one dummy bit line that outputs a leakage compensation current to at least one of the bit lines. A read current supply circuit outputs a read current necessary for a read operation to at least one of the bit lines in response to a first control signal. The memory device is a phase-change memory device containing phase-change material. The semiconductor memory device compensates leakage current in a read operation and supplies the leakage compensation current to a selected bit line, thereby suppressing error operation occurrence caused by leakage current.

Abstract: A data read circuit and method for use in a semiconductor memory device that has a memory cell array are provided. The circuit includes a selector for selecting a unit cell within the memory cell array in response to an address signal; a clamping unit for supplying a clamp voltage having a level for a read operation to a bit line of the selected unit cell in response to a clamp control signal; a precharge unit for precharging a sensing node to a voltage having a power source level in response to a control signal of a first state in a precharge mode, and compensating through the sensing node for a reduced quantity of current at the bit line in response to a control signal of a second state in a data sensing mode; and a sense amplifier unit for comparing a level of the sensing node with a reference level, and for sensing data stored in the selected unit cell.

Abstract: A drive circuit for a PRAM (phase-change random access memory) device includes a write driver that generates a set/reset current in response to a set/reset pulse. In addition, a temperature compensator controls a pulse width of the set/reset pulse in response to a peripheral temperature of the PRAM device. For example, the temperature compensator maintains the pulse width to be substantially constant irrespective of the peripheral temperature. In another example, the temperature compensator decreases the width for higher peripheral temperature.